Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 557 [Rate centres in NPA 557] [Dial plan for NPA 557]

NXX: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
557-557 A St Louis MO STLSMOWQDS2  093F ONVOY, LLC - MO 520      
557-557 0 St Louis MO   7432 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MO 520   2023-07-01   
557-557 1 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   
557-557 2 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   
557-557 3 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   
557-557 4 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   
557-557 5 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   
557-557 6 St Louis MO   7432 MCIMETRO ACCESS TRANSMISSION SERVICES LLC - MO 520   2023-07-01   
557-557 7 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   
557-557 8 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   
557-557 9 St Louis MO   093F ONVOY, LLC - MO 520   2023-06-14   

Last updated: Tue, 13 Jan 2026 21:50:02 UTC

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